ART: Convert pointer size to enum

Move away from size_t to dedicated enum (class).

Bug: 30373134
Bug: 30419309
Test: m test-art-host
Change-Id: Id453c330f1065012e7d4f9fc24ac477cc9bb9269
diff --git a/runtime/mirror/abstract_method.h b/runtime/mirror/abstract_method.h
index 936b14c..cfbe492 100644
--- a/runtime/mirror/abstract_method.h
+++ b/runtime/mirror/abstract_method.h
@@ -34,7 +34,7 @@
 class MANAGED AbstractMethod : public AccessibleObject {
  public:
   // Called from Constructor::CreateFromArtMethod, Method::CreateFromArtMethod.
-  template <size_t kPointerSize, bool kTransactionActive>
+  template <PointerSize kPointerSize, bool kTransactionActive>
   bool CreateFromArtMethod(ArtMethod* method) SHARED_REQUIRES(Locks::mutator_lock_)
       REQUIRES(!Roles::uninterruptible_);